Fbank g



(No MoaL) l l Ff G. STARK.

NUT; Y Je. 327,612. Pmentea 00t.6,18 85.

'MMM/V 45 my nut.

UNITED STATES .To aZZ whom it may concern,.-

Be it known that I, FRANK G. STARK, of the city and county of N ew York,in the State of New York, have invented certain new and usefulImprovements in Nuts, of which the following is a specification.

My improved nut has an annular projection on one face, constitutinga rimencircling the threaded hole. The hole is screw-threaded, as usual, tomatch the bolt.` The exterior of the annular rim is also screw-threaded.In what I esteem the most complete form of the invention the exteriorthread varies a little in pitch from the interior thread.

other ordinary material. It may apply against wood in the manufacture ofbuildings, bridges, ship, and steamboat framing, and the like. It mayapply against cast-iron or any other material. The hole should bepreviously bored to facilitate' the reception of the projection. Underordinary conditions, when the nut is in use, it has a plane face ofconsiderable area which presses against a corresponding plane surface ofthe wood or metal, or against a washer or loose collar which isinterposed. Its threaded projection also matches into the cavity, whichis an enlargement of the ordinary hole which receives the bolt incast-iron or other metal, or in hard wood. The cavity should be threadedby a tap or other suitable device before the nut is inserted. In softwood,

- as pine or spruce, the hole may be left plain,

and on bringing the nutinto position and turning it forcibly thescrew-threaded exterior of its rim will produce a sufficient thread inthe cavity.

The following is adescriptiou of what Iconsiderthe best means ofcarrying out the in- 4o\veetion.

The accompanying drawings form a part of this specification.

Figure l is a side View, Fig. 2 an end view, and Fig. 3 a cent-rallongitudinal section, of Figs. 4, 5, and 6 represent the nut in use.They are longitudinal sections. Fig. 4 shows the nut firmly inserted in.the materialwhich it is to aidiu confining. shows the hole previous tothe insertion of Application filed October 23, 1884. Seria-l No.146,255.

My improved nut may be made of iron or Fig. 4ta' PATENT @Errore FRANK G.STARK,IOF NEWY YORK, N. Y.

NUT.

, SPECIFICATION forming part of Letters Patent No. 327,612, datedOctober 6, 1885.

(No model.)

this condition the nut is performing its usual principal function, thatof strongly engaging with the bolt. Fig. 6 shows the nut partlyunscrewed. This represents the condition when the nut is used fordelicate adjustment of the tension on the bolt.- Fig. 7 is alongitudinal section through a form of the nut more especially adaptedfor use in iron machinery. Fig. 8 shows another modification.

Similar letters of reference indicate corre* spending parts in all thefigures.

I will describe my nut and its connected bolt as applied to holdtogether certain parts of a bridge-framing or analogous stout structureof wood.

A A', &c., are timbers which. it is desired to hold.

B is a screw-bolt. Bis a head for such bolt. The other. end of the boltis screwthreaded and adapted to engage with my nut, or with any otherordinary nut.

D is my improved nut, certain lportions being designated, whennecessary, by additional marks, as D D2. The body of the nut is markedD. D2 is a threaded projection surrounding the threaded hole d. lf thenut is intended for use with an iron frame, the exterior of theprojection D2 may be nearly cylindrical. Il' the nut is to be used withsoft wood, it may be tapered to the extent shown, or something more orless. For either situa-l tio'n'the exterior of the projection D2 isscrew threaded.

In what Iesteem the generally preferable construction the malescrew-threads di 'on 85 the exterior of the projection D2 are of alittle greater pitch than the female screw-threads in the interior ofthe bolt-hole d. A cavity to receive the projection'being previouslybored, the nut is iirst applied so that its screwthreads di engage inthe cavity in the wood, and'screwed home. As the threaded projection D2sinks into the slightly smaller recess in the wood it producesclearly-defined threads in the wood corresponding to the threads in thescrew. The parts should be soproportioned that as the bottom face of therectangular pon tion D bears on the upper face of the part A theprojection D2 is embraced very tightly in the material of A. The bolt BB is then inroo 5o the nut. Fig. 5 shows the bolt in place. l In sertedfrom below, and turned by a wrench or other suitable device to engagetightly with the screw-threads of my nut. The friction induced by thetight grip of the material on the 5 projection D2 prevents the nut fromever Working loose under any circumstances.

For use on metal, as in holding together the cast-iron parts of a largeprinting-press or other machine. the recess to receive the pro- Iojection D2 is bored or otherwise produced cylindrical] y, and screw-threads are impressed by hand or by machinery having a correspondingcylindrical character. In other words, the screw does not taper.

When the nut is made for use in wood-work, or when in any material whereit is to cutits own thread, I prefer it should taper. The

, amount ot' taper may be varied.

The form of this nut involves peculiar effects in the working which areof marked advantage. The depth of the available port-ion of the nut tohold on the bolt is increased by the presence of the projection D2. Thefriction of the nut on wood or other material, A, is much greater thanthe friction of an ordinary nut of corresponding size. The hole toreceive the projection Dl should be bored out only to a sufficient sizeto allow the projection D2 to be properly entered. There should be atight grip of the wood on the screwthreads di. The friction thusgenerated prevents the nut from shaking loose. Bolts having my nutsproperly applied will endure any amount of ordinary or extraordinaryjarring without becoming loose. Mattach importance to the fact that theprojection D2 is continuous, or not split. Nuts have been before madefor special purposes with a split conical projection adapted to becompressed tightly together upon the bolt by acting forcibly on theexterior with an inclosing-nut. ll/Iy nut is radically different, notonly in the mode of using and in the absence of the inclosing-nut, butin the fact that .the projection is, by reason of its undividedcondition, able to withstand any amount of compressing force withoutbeing sprung inward.

Modifications may be made in the forms 5o and proportions withoutdeparting from the principle or sacrilicing the advantages of theinvention. Iarts may be used without the whole.

By producing the screw-threads d2 on the exterior of the projection D2of exactly the I produce a nut having the same general appearance, andwhich may be used in the same manner as above described. It will havethe same effect, so far as strongly holding the bolt is concerned,providing the direction is followed that the nut be first tirmlyinserted quite down to its bearing and that same pitch as the threads inthe bolt -hole d the bolt be afterward screwed into it from within; butit will then fail to possess any facility for adjusting the tension.Such anut may, as will be obvious on reflection, be unscrewed to aconsiderable extent without changing the tension on the bolt. It canalways be screwed down, so as to bring the square portion D to a fairbearing on the outer face of the wood. On the other hand, instead ofmaking only a slight difference in the pitch between the exteriorthreads, d2, and the interior threads of the nut, I can gi've a greatdifference to the pitch, or even can make the exterior threadsleft-handed, while the interior threads are right-handed. This lattergives a very rapid change of tension on the bolt as the nut is adjustedoutward or inward. Au objection to this lies in the fact that it is notpracticable always to obtain with such nut a fair bearing of the mainbody of the nut against thewood.

It will be readily understood that my nut may be backed by another nut,serving therewith as a jam-nut, in cases where extraordinary precautionsagainst loosening are required; but I do not propose, generally, to usesuch. The friction produced by the em- 9o bracing of my nut by the'surrounding material renders a jam-nut unnecessary. It is a chief meritof my invention that it will hold firmly Without a jam-nut,and withoutany mutilation or distortion of any part.

I can make my nut with a closed end, or what is sometimes known as a boxend. Such may be useful on the axle of carriages and in othersituations.

Fig. 8 shows a form in which this feature IOO is embodied. This nut isalso formed with a flange, which, when the nut is in use, presents theappearance of a washer under an ordiy, nary nut.

I claim as my invention- 1. The nut described, having the undividedprojection DZin the acting face adapted to generate friction in thematerial against which it acts without allowing itself to be compressed,all substantially as herein speci- IIO fied.

2. A nut having a projection, D2, and provided with a screw-thread, d2,on the exterior of a different pitch from the interior threads, incombination with the bolt B B, and tim- IIS bers or other articles ormaterial, A A2, to be confined, arranged for joint operation as here` fin specified. y

In testimony whereof I have hereunto set my hand, at New York city, this15th day of I2O t October, 1884, in the presence of two subscribingwitnesses.

FRANK G. STARK.

Vitnesses: Y*

J. E. RENWEE, CHARLES R. SEARLE.

